1. Field of the Invention
The present invention relates to a switching power supply device.
2. Description of Related Art
Some of the conventional switching power supply devices are provided with a power saving mode (a so-called burst mode) in which the switching driving of an output transistor is suspended under a null or extremely light load.
An example of the conventional arts related to the above is disclosed in Japanese Patent Application Publication No. 2002-315333.
However, with such conventional switching devices, there has been a demand for further reduction of the power consumption also when the load is light but not light enough to cause a mode shift to the burst mode.